| 摘要 |
<p>1,084,005. Hoisting tackle. RICHIER, S.A. June 22, 1966 [June 22, 1965], No. 27993/66. Heading B8B. The hoisting tackle of a tower crane comprises a rope 30 passing around upper and lower sets of pulleys 16, 23 and a further pulley (20) movable between the lower and upper sets of pulleys to provide two or four falls respectively. The upper pulley framework 14 mounts a pair of spaced parallel plates 18 held in their respective position by a spring (19) and each having a bearing hole 21. The further pulley framework 25 mounts a pair of spigots 27 which on raising the further pulley assembly 12 forces the plates 18 apart until the spigots 27 are engaged by the holes 21. The further pulley assembly 12 is released from the plates 18 by an arm 29 movable between an inoperative position and an operative position in which on raising the lower pulley assembly towards the upper pulley assembly the plates 18 are forced apart by the arm 29 to release the spigots 27 from the holes 21. The dimensions of the arm 29 are such that the further pulley assembly and the lower pulley assembly may be lowered without further engagement with the holes 21.</p> |
